I Smell Hungry — Beckman 2006 (309): 2
To find out, Brodie and colleagues looked at parental feeding behavior in burrower bugs (Sehirus cinctus). Adults are about the size of a pencil eraser, and the youngest babes–there can be up to 100 per brood–look like bright red pinheads. The researchers separated the babies into two groups: One got plenty to eat, while the other was underfed. They then collected the volatile chemicals wafting from each clutch. Finally, using a “smell-o-tron,” the researchers blew these odors toward mother bugs.
Moms receiving odors from ill-fed babies immediately set to finding more food. Mothers gassed with sated-baby odors, on the other hand, slowed their food search.